Exercice physique, carence estrogénique, monoxyde d'azote et remodelage osseux

Summary

Objectives

The aim of this paper is to emphasize the possible relationships established between estrogens and physical exercise and concerning bone metabolism. Nitric oxide (NO) might play an important role in such relationships.

Topics

Cellular metabolism of NO, as well as NO effects upon osteoblasts and osteoclasts have been summarized. Several studies indicate that NO deficiency might be implicated in various vascular diseases observed in post-menopausal women. Other works also indicate that NO deficiency induced by cessation of ovarian activity might be responsible for osteopenia associated with this condition. Thus, decreased production of NO would be responsible both for post-menopausal osteoporosis as well as for osteopenia sometimes observed in amenorrheic athletes. Moreover osteoblastic response to mechanical stimulation might implicate estrogenic receptor(s). The role of these receptors in the regulation of NO synthesis is still unknown.